Many types of bearings can be used to support radial, thrust, or combination radial and thrust loads. Such bearings include ball, roller, plain, journal and tapered roller bearings. Typically, rolling bearings include an outer ring having a generally cylindrical exterior surface and a generally cylindrical inner surface defining an interior area of the outer ring. An inner ring having a generally cylindrical outside surface is disposed in the interior area of the outer ring. A plurality of rolling elements, such as balls or needle rollers are disposed in a cavity between the outside surface of the inner ring and the inner surface of the outer ring.
The outer ring and/or the inner ring can rotate relative to one another. For example, the inner ring may be secured to a shaft and the outer ring can rotate relative to the inner ring and the shaft. During rotation of the outer ring and/or the inner ring relative to one another, the bearing may be subject to cyclic loads that could cause fatigue failure of the bearing. Fatigue life of bearings can be represented as a “L10” life. This is the life at which ten percent of the bearings in that application can be expected to have failed due to classical fatigue failure or, alternatively, the life at which ninety percent will still be operating. The L10 life of the bearing is the theoretical life.
Some bearings are subject to high load rates and/or high rotational accelerations rotations that could cause the rolling elements to slip, skid and/or cause backlash of the rolling elements in the outer ring and/or the inner ring. Such slippage, skidding and backlash could degrade bearing performance and result in premature failure of the bearing.